/*
 * ZoomGestureDetector.java
 * Android-Charts
 *
 * Created by limc on 2014.
 *
 * Copyright 2011 limc.cn All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


package cn.limc.ohoscharts.event;


import ohos.multimodalinput.event.MmiPoint;
import ohos.multimodalinput.event.TouchEvent;

/**
 * <p>en</p>
 * <p>jp</p>
 * <p>cn</p>
 *
 * @author limc
 * @version v1.0 2014/06/20 17:33:01
 */
public class ZoomGestureDetector<T extends IZoomable> extends TouchGestureDetector<ITouchable> {

  public static final int TOUCH_MODE_NONE = 0;
  public static final int TOUCH_MODE_SINGLE = 1;
  public static final int TOUCH_MODE_MULTI = 2;

  public static final int MIN_DISTANCE = 5;

  protected int touchMode = TOUCH_MODE_NONE;

  protected float olddistance;
  protected float newdistance;

  protected OnZoomGestureListener onZoomGestureListener;

  public ZoomGestureDetector(IZoomable zoomable) {
    super(zoomable);
    if (zoomable != null) {
      onZoomGestureListener = zoomable.getOnZoomGestureListener();
    }
  }

  protected float calcDistance(TouchEvent event) {
    MmiPoint point = event.getPointerPosition(event.getIndex());
    if (event.getPointerCount() <= 1) {
      return 0f;
    } else {
      float x = point.getX();
      float y = point.getY();
      return (float) Math.sqrt(x * x + y * y);
    }
  }

  @Override
  public boolean onTouchEvent(TouchEvent event) {
    //此出 switch (event.getAction() & MotionEvent.ACTION_MASK) {
    switch (event.getAction()) {
      case TouchEvent.PRIMARY_POINT_DOWN:
        if (event.getPointerCount() == 1) {
          touchMode = TOUCH_MODE_SINGLE;
        }
        break;
      case TouchEvent.PRIMARY_POINT_UP:
        touchMode = TOUCH_MODE_NONE;
        break;
      case TouchEvent.OTHER_POINT_UP:
        touchMode = TOUCH_MODE_NONE;
        break;
      case TouchEvent.OTHER_POINT_DOWN:
        olddistance = calcDistance(event);
        if (olddistance > MIN_DISTANCE) {
          touchMode = TOUCH_MODE_MULTI;
        }
        return true;
      //break;
      case TouchEvent.POINT_MOVE:
        if (touchMode == TOUCH_MODE_MULTI) {
          newdistance = calcDistance(event);
          if (newdistance > MIN_DISTANCE
                  && Math.abs(newdistance - olddistance) > MIN_DISTANCE) {
            if (onZoomGestureListener != null) {
              if (newdistance > olddistance) {
                onZoomGestureListener.onZoomIn((IZoomable) instance, event);
              } else {
                onZoomGestureListener.onZoomOut((IZoomable) instance, event);
              }
            }
            olddistance = newdistance;
          }

          return true;
        }
        break;
    }
    return super.onTouchEvent(event);
    //		return true;
  }

  /**
   * @return the onZoomGestureListener
   */
  public OnZoomGestureListener getOnZoomGestureListener() {
    return onZoomGestureListener;
  }

  /**
   * @param onZoomGestureListener the onZoomGestureListener to set
   */
  public void setOnZoomGestureListener(OnZoomGestureListener onZoomGestureListener) {
    this.onZoomGestureListener = onZoomGestureListener;
  }
}
